1. Field of the Invention
The invention relates to a bowling pin storage bin for use as part of a bowling pin delivery system of a pinspotter apparatus, as well as a method of manufacturing such bin. More particularly, in a particular embodiment, the storage bin of the invention is molded as a one-piece article having a plurality of cavities or pockets for storing bowling pins in an essentially horizontal plane above a pin spotter and for delivering the pins to a plurality of pin cups or a pin spotter for spotting on a pin deck.
2. Description of Background and Relevant Information
A pin spotting apparatus performs a number of conventional functions in the sport of bowling, and it includes the necessary mechanical and electrical components therefor. Included in these functions are stopping the bowler's ball, returning the ball to the bowler, setting the pins at the beginning of a frame, and resetting pins for a second ball of the frame if a strike is not scored.
During successive bowling frames, the pins which are knocked down and pins that remain standing after each frame are generally delivered directly to the spotting machine or to a storage device from which pins are supplied on demand. The mechanical components of a pin spotting apparatus include the cushion, which stops the ball and deflects it to the pit area to be returned to the bowler; the sweep, which removes fallen pins from the pin deck and adjacent gutters; the carpet, which is a belt that carries the fallen pins to the pin elevator, where they are can-led up to the distributor; the pin elevator, which carries the pins from the pit area and delivers them to the distributor; the distributor, which delivers the pins from the pin elevator to the bin assembly; the ball lift, which lifts the ball to a height that will enable gravity to return the ball to the bowler; the bin and shuttle assembly, the bin of which stores pins received from the distributor until the pins are ready for spotting, and the shuttle of which is movably mounted beneath the bin to allow stored pins to be dropped into the pin-spotting table; and the pin-spotting table, which performs the spotting and re-spotting functions by means of two assemblies, i.e., the yoke assembly, which supports ten spotting cups, and the table assembly, which houses ten re-spot cell assemblies. Once the pins are spotted, or re-spotted, the lane is ready for the game to continue or for a new game to begin.
It is desirable to provide pins to the pin spotting machines rapidly so that a game of bowling can be played swiftly without undue delays. It is important, therefore, that the pin distributing system keeps pace with the spotting machine and provides pins rapidly thereto and in a position for spotting on the pin deck. It is also important that any such mechanism minimize the likelihood of jams, misplaced pins or other failure which would take an alley out of service and/or cause and unacceptable delay in a game of bowling.
Prior bowling pin distribution systems include the system disclosed in U.S. Pat. No. 3,248,109.That system includes a mechanical pin distribution structure combined with an electrical operating system for programming the sequence of pin distribution. The distributor includes a conveyor having a cantilevered arm which swings transversely above a receiver to which pins are delivered. The principal mechanical parts other than the swinging distributor are simple elements which deflect pins to assigned locations in the receiver. The distributor is indexed to move successively to various positions by a central control system to appropriately distribute the pins to the receiver.
The receiver of the U.S. Pat. No. 3,248,109 system includes a storage section, or storage bin, that defines a plurality of ten pin-receiving pockets arranged in a pattern that conforms to the regulation array of pins spotted on a bowling alley. The storage section is supported from beneath by a frame, the frame and storage section being positioned below the distributor and above a spotting table. Each of the ten pin-receiving pockets is bottomless and the opening at the bottom of the pocket is obstructed by one of a plurality of bin cups. Each of the bin cups has an internal shape which is compatible with that of a bowling pin and, when positioned, is adapted to cradle a bowling pin. Subsequently, the cups rotate to drop their pins to be positioned on the spotting table.
U.S. Pat. No. 3,526,410 discloses a similar system. Pin storage bins of the pin distribution systems of both of these patents are made from sheet steel and various ancillary components.
FIG. 1 of the attached drawing illustrates an example of a known pin spotter bin 1, constructed largely of sheet steel from hundreds of parts, having ten pin cavities 2a-2j. Among these many parts are pin guides 3 within the cavities, bin assembly brackets 4 with bumpers 5, spacers 6, left and right pin guides 7, 8, pin butt guides 9, channels 10, 11 and stringers 12 between the channels, as well as a multitude of springs, nuts, bolts, sleeves, brackets, etc. The metal bin of FIG. 1 holds twenty pins (not shown), one in each cavity as well as a second layer of ten pins lying on top of the cavity-held layer of ten pins.
As an improvement over the aforementioned bowling pin distribution systems, which are largely manufactured from sheet steel and various ancillary components, U.S. Pat. No. 5,439,418 discloses a storage bin, or pin-spotter bin, molded from plastic. Intended advantages of this storage bin were to include a simplified design, enabling the system of which it is a component to require fewer parts, therefore contributing to durability of the system, facilitating and minimizing maintenance, thereby reducing alley down time. In addition, the disclosed bin was intended to be relatively easy to manufacture and install, both at a relatively low cost compared to the prior storage bins. Further, a plastic bin would reduce noise caused by pin impacts during use, and the surfaces of the pins would not be marred or scratched as they are during impacts with current metal bins. The specification of U.S. Pat. No. 5,439,418 explains that a rotational molding method of fabrication, sometimes referred to as “rotomolding,” can be used to make a plastic bin according to the disclosure, using a linear low-density polyethylene (LDPE).
Despite the intended advantages of the storage bin of U.S. Pat. No. 5,439,418 and advances that would be made over the prior art and bins in current use, problems have been identified that prevent such molded bins from functioning optimally and that have prevented such a bin from becoming commercially acceptable.
Rotational molding, which relies upon gravity acting upon molten plastic inside a mold, is known to be used for the manufacture of large, hollow-shaped articles, such as boat hulls, fuel and storage tanks, shells for luggage, and various types of containers. A quantity of polymer powder is loaded into the interior of a two-part mold, which is then heated and rotated simultaneously about two perpendicular axes, thereby spreading the polymer particles onto all internal surfaces of the mold, the heated polymer becoming fused into a single melted layer. While continuing to be rotated, the mold is then cooled so that the plastic layer becomes solidified. The mold is then opened and the plastic article is removed.
Because the coating of the internal walls of the mold with the melted plastic is done by gravity rather than by centrifugal force, rotational speeds are relatively slow. However, rotomolding is typically preferred for making articles that have more complex geometries, for relatively larger articles, and ones that have lower production quantities than, say, blow molding or related molding processes that are used to make hollow parts from thermoplastics. Accordingly, the one-piece bin of U.S. Pat. No. 5,439,418,which is a hollow piece having a relatively complex geometry, is disclosed as being made by rotomolding. Mention is made that another method of fabrication could be used, although not described. U.S. Design Pat. No. 366,510 provides further views of the bin.
U.S. Pat. No. 5,439,418 cites low-density polyethylene (LDPE) as an example of a material from which the bin can be made by the disclosed process of rotomolding. However, due to the nature of the rotomolding process and the hollow structure that characterizes the article produced by that process, even high-density polyethylene (HDPE), regarded by persons skilled in the technology as the best material that could be used, i.e., providing somewhat greater stiffness at a somewhat greater cost, does not have the necessary impact resistance to create a bin that could function very long without cracking or succumbing to material fatigue.
In addition to potential problems associated with the materials and the construction of the bin of U.S. Pat. No. 5,439,418,the particular geometries of the ten pockets, or cavities, disclosed therein are not found to be optimum in efficiently receiving pins from the distributor for being temporarily stored and made ready for being fed to the spotting table.